1. Field of the Invention
The present invention is related to a stereoscopic video processing method and a stereoscopic video processing apparatus for processing stereoscopic videos. The present invention is also related to a program that causes a computer to execute the stereoscopic video processing method.
2. Description of the Related Art
It is known that stereoscopic viewing that utilizes parallax is enabled by combining and displaying a plurality of images. Stereoscopic images that enable stereoscopic viewing may be generated by obtaining a plurality of images of a single subject using a plurality of cameras at different positions, then combining a plurality of images utilizing the parallax of the subject included in the plurality of images.
Specifically, stereoscopic images may be generated by causing colors in the plurality of images to be different, such as red and blue, then overlapping the images. Alternatively, stereoscopic images may be generated by causing the polarization directions to be different within the plurality of images, then overlapping the images. In these cases, stereoscopic images can be viewed three dimensionally, by viewers' eyes stereoscopically viewing the stereoscopic images, which are displayed using red/blue glasses or polarizing glasses, using the automatic focusing function of the eyes (the anaglyph method and the polarizing filter method).
It is also possible to view stereoscopic images three dimensionally without using polarizing glasses and the like. The parallax barrier method and the lenticular method enable stereoscopic images to be viewed three dimensionally, by displaying the stereoscopic images on a three dimensional liquid crystal display. In these cases, the stereoscopic images are generated by cutting the plurality of images into vertically extending stripes, which are then arranged alternately. Another example of a stereoscopic display method is the time division method, in which the light beam directions of left and right images are changed by the use of image separating glasses or by attaching optical elements to liquid crystal displays, and displaying the right and left images alternately.
A technique for setting the type of display to be performed in advance when reproducing stereoscopic videos has been proposed (refer to Japanese Unexamined Patent Publication No. 2004-200813). According to the technique disclosed in Japanese Unexamined Patent Publication No. 2004-200813, settings may be set such that a two dimensional video which cannot be viewed three dimensionally is displayed for the first several seconds, and then display is switched to stereoscopic display.
A technique for resolving disorientation experienced by viewers during switching between three dimensional display of stereoscopic videos and two dimensional videos, which cannot be viewed three dimensionally, in cases that both types of images are present, has also been proposed (refer to Japanese Unexamined Patent Publication No. 2004-328566). According to the technique disclosed in Japanese Unexamined Patent Publication No. 2004-328566, switching between three dimensional display and two dimensional display is performed gradually, in order to reduce disorientation experienced by viewers.
When stereoscopic videos are filmed, scenes change when operations such as initiation of filming, cessation of filming, change of zoom magnification rates, and the like are performed. As a result, the perceived depth changes prior to and after positions within the stereoscopic videos at which scene changes occur. However, in three dimensional viewing, depth perception is realized by the automatic focusing function of viewers' eyes. Therefore, viewers will become extremely fatigued if the perceived depths of scenes switch suddenly. The technique disclosed in Japanese Unexamined Patent Publication No. 2004-200813 sets the manner in which two dimensional videos and stereoscopic videos are to be displayed in advance. Therefore, this technique cannot be applied to scene switching within stereoscopic videos. The technique disclosed in Japanese Unexamined Patent Publication No. 2004-328566 switches between three dimensional display of stereoscopic videos and two dimensional display of to dimensional videos gradually. Therefore, this technique cannot be applied to scene switching within stereoscopic videos.